Lifelong learning: what did you learn this week?

[jhbratton]

I have just watched a superb documentary on BBC 4 tonight called The Birds, about a retired wildlife cameraman filming the interactions between wading birds and peregrines on the Norfolk coast. But the lifelong learning part was his assertion that the intricate pattern of pools in mudflats is due to the tiny but super-abundant snail Hydrobia ulvae eating the diatoms on sand grains, which makes the sand grains less sticky and more mobile. Are there any saltmarsh ecologists here who can verify that please?